In a magnetic recording method utilizing residual magnetic effect, a permanent image (or a hard copy) is obtained through the following four steps:
(1) A magnetic latent image is formed on a magnetic member;
(2) The latent image is developed with a magnetic toner or coloring particles affected by a magnetic field, the magnetic toner or coloring particles being prepared by mixing magnetic particles in a high molecular resin;
(3) The developed image is transferred onto a recording sheet or the like according to an electrostatic method or a magnetic method; and
(4) The transferred image is fixed with heat or pressure into a permanent image (hard copy).
In the above-described magnetic recording method, after removal of the magnetic toner, the magnetic recording medium bearing the magnetic latent image is supplied to the next developing operation, or the magnetic latent image is erased to form a new magnetic latent image, so that the same process may be carried out again.
With respect to this magnetic recording method, there have been proposed a variety of methods of forming magnetic latent images. Among these conventional methods is a so-called "thermomagnetic recording method" in which thermal inputs are utilized to form magnetic latent images. In this method, an inexpensive heating array can be used as the latent image forming means.
With respect to a latent image forming method in the above-described thermomagnetic recording method and a thermomagnetic recording medium used therein, Japanese patent application No. 37865/1981 describes an invention which makes an external bias magnetic field unnecessary, and produces an image of excellent quality by developing a latent image with powder.